The invention relates to improvements in machines for placing inserts (hereinafter called stuffers) between the panels of folded sheets, especially for placing stuffers between the halves of main sections or other sections of newspapers.
Swiss Pat. No. 594 552 discloses a machine wherein a set of pocket-shaped equidistant receptacles is transported along an endless path past a unit which inserts folded sheets into successive receptacles before the receptacles reach an opening station where the inserted sheets are opened, i.e., their panels are pivoted relative to and away from each other preparatory to admission of stuffers into the spaces between the panels of the thus opened sheets. The means for opening the folded sheets comprises a sword-like tool which is caused to penetrate between the panels of a sheet and to pivot the panels in a direction to open up the sheet for reception of a stuffer. The arrangement is such that the sword must be located at a predetermined distance from one wall of the receptacle for the folded sheet which is about to be opened. This ensures that, if one panel overlies the one wall, the sword will penetrate between the panel which overlies or abuts the one wall and the other panel. The patented machine will operate properly only if the receptacles are rigid, if the dimensions of each receptacle match a predetermined norm and if each receptacle invariably assumes a predetermined position in its endless path when the sword is caused to penetrate between the panels of the folded sheet in such receptacle. This cannot be readily achieved if the endless path is relatively long, i.e., if the machine comprises a large number of receptacles. Moreover, and if the machine is to be set up to insert stuffers between folded sheets having panels of different thicknesses, the time for changing the setup is very long because each and every sword must be individually adjusted with reference to the walls of the corresponding receptacle. Furthermore, the number of parts which are necessary to ensure proper adjustment of each individual sword is very large and all this contributes to bulk, complexity and cost of the machine. Thus, it is desirable to provide a machine which can be rapidly converted for the processing of folded sheets having panels of different thicknesses, particularly a machine which can be used to stuff newspapers wherein the thickness of main sections or other sections which are to receive stuffers often changes from day to day.